Another Displacement query

[pgatsky]

Hi all
I recently put a thread up on here to ask about displacements and some of the problems Im getting with them within octane and I thank jayroth for his brilliant answers to my queries, very informative.

I have another, and probably related. When I displace on glass, which is more often than not, ive noticed that its hard to get it to look really smooth and not speckly round the edges.

I've attached a file again and some screen shots to show what i mean. I've adjusted the image so its 32bit etc but have found that no matter how long I render it for it never really improves that much. Its like its pixalating or something similar but yet again im using a hires image with the settings at around 4k but it still doesn't help. Ive also tried making the image being used as the displace much softer but that also isn't working and if anything makes it worse.

So my question is, is this something that will just get better by letting it render for thousands and thousands of passes or is there something im missing with the settings?

Any further help will be highly appreciated.

Thanks

[pgatsky]

Any thoughts on this one people? Its a problem that ive come up against a number of times so any input will be welcome.

[frankmci]

Part of the problem looks like the fact that the letters in your displacement texture are only 80 pixels high. That's not much data for the displacement to work with. Here's a shot of the same setup, with a 1k x 8k texture, so that the letters are about 600 pixels high. The refraction is handled much better, I think you'll agree.

[jayroth2020]

Frank is correct. In the displacement game, it's all about resolution: displacement map size and color depth (bits per pixel).

[pgatsky]

Thanks guys thats really useful information to know.